Software evolution research has focused mostly on
analyzing the evolution of single software systems.
However, it is rarely the case that a project exists
as standalone, independent of others. Rather,
projects exist in parallel within larger contexts in
companies, research groups or even the open-source
communities. We call these contexts software
ecosystems, and on this paper we present The Small
Project Observatory, a prototype tool which aims to
support the analysis of project ecosystems through
interactive visualization and exploration. We
present a case-study of exploring an ecosystem using
our tool, we describe about the architecture of the
tool, and we distill the lessons learned during the
tool-building experience.